Build Your Own Sandbox

My kids had outgrown the old 4′ x 4′ sandbox that hides under our playset. It’s only 4 inches deep, and bark is constantly pouring over the sides and into the sand. Since our 2 year-old spends hours in the sand each day, we decided it was time for an upgrade– and a new type of adventure. After seeing a really cool sandbox at my neighbor’s house, I made some measurements and went to work. The sandbox was easy, fairly cheap, and the end product is really cool.

The great thing about the design for this sandbox is that the lid also serves as a bench. So when the sandbox is closed, it is closed tightly. The old sandbox had a heavy, unwieldy lid that we eventually stopped using, turning our sandbox into an occasional litter box– even though we don’t have cats. When you open the lid on the new sandbox, it folds back into a bench on either side, sturdy enough for Mom and Dad to sit on. Here are complete instructions for building the sandbox of your dreams:

Now you can play in the sandbox, too!

Tools you’ll need:

A “chop” saw or miter saw

A power drill with 1/8″ bit and Phillips head bit

Wood you’ll need:

11: 2×6 boards that are 10 feet long

4: 2×6 boards that are 8 feet long

4: 2×4 boards that are 8 feet long (see comments below. I was able to use some scraps I had laying around)

Hardware you’ll need:

4: 4 inch T-hinges (pictured below)

4: 11 inch regular hinges (pictured below)

125 (or so): 2.5 inch wood screws

20 (or so): 1 inch wood screws if your hinges don’t come with screws

4: handles

1-2: gallons of Deckover or other exterior wood paint

If you want to make sure you get the right parts, I’ve put an Amazon link where you can check out or order the parts at the end of this entry.

A standard 11″ hinge. You can also use an 8″ hinge.

The 6″ T-hinge is actually 7″ long and 4″ high.

Total time I spent on the project including painting, cutting, and assembly: 8 hours

Total cost: about $200

Step 1: Cutting

The cutting on this project is simple, but if you don’t have a miter saw (what I call a chop saw), most hardware stores will make cuts for you for a small fee.

Take all 11 of your 10 foot 2×6’s and cut them in half with the miter saw giving you 22 2×6 that are 5 feet long. This is the width of the sandbox. Leave the four 8 footers alone, that’s the length of the box.

You’ll need 22 of these: 2×6’s that are 5 feet long.

You can cut two of the 2×4’s at the same time with the saw. This assures the pieces are the same length and saves you some cuts, so carefully stack two 2×4’s on the saw and cut the following:

4 lengths of 30 inches (so measure 30″, chop, repeat, should give you 4 from the stacked boards). You’ll use these to support the back of the bench.

4 lengths of 14.5 inches (so measure 14.5″, chop, repeat should give you 4). You’ll use these as “armrests” on the bench.

Using the third 2×4, cut four 11 inch pieces. You’ll use these as corner supports.

(Optional): I wanted my armrests to be beveled on the outside end rather than squared off. I measured 1 inch from the bottom of the 2×4 and one inch from the end. Then I drew a line to connect the marks. Then I used the saw to cut along the line. You can see the bevel in the picture.

You can see the bevel I put on each “armrest” on the right end of this picture.

Step 2: Painting

My least favorite part of any project is painting. Here are a few tips: Lay plastic on the garage floor and set up small scraps to lay the wood on. I tried both rolling and brushing with a 3 inch brush, and I like the rolling better. The deckover I used dried fast, so I could (gently) flip and paint boards after about 20 minutes. Paint all sides, ends, etc. and let them dry for 2 days.

Redwood Deckover (not the spray paint in the can).

Step 3: Assembling the box

For this step you’ll need 4 of the 5 foot lengths, all 4 of the 8 foot lengths, the 11 inch 2x4s, and some 2.5 inch screws. On a flat surface, stand up one of the 8 foot lengths on it’s edge. Place one of the 5 foot lengths at the end so that your screw will go through the five foot length into the end of the 8 foot length. Drill two guide holes with the 1/8 inch bit. (If you don’t, you’ll run the risk of splitting the end board as you are working very near the end). Then use 2 screws to secure the boards. Repeat this process on each of the corners until you have built the bottom level of the box. Remember: screws go through the 5 footer into the ends of the 8 footer.

Now you’ll repeat the steps by assembling the second layer of the box on top of the first. Don’t worry too much about it lining up perfectly yet. You can even build level 2 on flat ground and lift it on top of level one at the end.

This shows the two levels stacked together. You can also see how I rotated the 11 inch pieces.

When the 2 levels are stacked, place one of the 11 inch 2×4’s in each corner standing on end. These boards will secure the 2 layers together. I choose to alternate them as I went around clockwise. So in corner 1, the flat side of the 2×4 goes against the 5 footer; in corner 2 the flat side goes against the 8 footer; in corner 3 the flat side goes back against the other 5 footer, and in corner 4 the flat side goes against the other 8 footer (think rotational symmetry rather than mirror symmetry). I’m not sure this matters, so don’t get hung up on it– it certainly won’t show in the final product.

The 2x4s in the corner shown from the inside.

Drill guide holes from the outside of the box with the 1/8″ bit and add 4 screws in each flat side and 2 in each short side of the 2×4. It is always a good idea to NOT align the screws vertically as you can split the wood if you do. Once you’ve added six screws to every corner, your box should be very sturdy.

The board on the left is the 5 footer. In this corner, the 2×4 on the inside has the flat side against the 8 footer. So on the left, only 2 screws go into the 2×4, the other 4 go into the 8 footer. Notice the screws are not aligned.

Here’s the inside corner with the flat side against the 5 footer (end of the box).

Step 4: Assembling the seats

To assemble the 2 seats, you need 6 of the remaining 5 footers and the 2 armrests. Lay the armrests nearly 5 feet apart with the top side down (this only matters if you beveled them). Place three of the 2x6s across them. Square the 2x6s so all the ends are even. Measure in 3 inches from each end and draw a light pencil line. Then carefully adjust the armrest underneath until the board is centered on the line. I measured in 1 inch from the “back” of the seat (the opposite of the beveled end) so the armrests would look uniform, but you could eyeball it and be fine. Finally use 6 of the 2.5 inch screws (2 on each board) to secure the armrest on each end. Place the screws slightly off each side of the line so they are not all in an exact line, which may split the wood. Repeat this process for both ends, and then for the second seat.

This shows the placement of the screws in the seat.

Step 5: Assembling the seat back

The seat back assembly is almost exactly like the seat assembly. Lay the two 2x4s about 18 inches apart. Then lay 3 of the 2x6s across them. Measure 21 inches from the end of the 2x6s and make a light pencil line. Line up the 2x4s centered on the line. Exactly 14 inches of 2×4 should extend below the 2x6s. Then attach the screws as described in Step 3.

The finished seat back. There’s 18 inches between the 2x4s and 14 inches of 2×4 hanging over the 2×6.

Step 6: Attaching the seat to the back

First, lay the seat back with the long 2 by fours underneath exactly as they were at the end of Step 4. Then lay the seat on top of the 2x4s snugly against the other 2x6s with the armrests up. Make sure everything is aligned. If you beveled the armrests so there is a front, the front should go to the outside near the end of the 2x4s. Finally, lay the T-hinge with the square end on the seat and the triangular end on the back and attach with the screws provided (if no screws came with your hinge, use 1 inch screws). Make sure that the hinge is positioned so that the seat folds UP toward you and away from the 2x4s on the seat back. Repeat this step with the other seat and back.

This is how it looks when you screw the hinges in.

And here is the seat folded up with the backrest laying on the ground.

Step 7: Finishing up

You’ll want to make sure your sandbox is level and clear the ground underneath. You may even want to put weed mat down. When the frame is set, lay out the top in the following order: 3 of the loose 2x6s, the seat bottom, and the seat back with the 2x4s up. Then mirror that with the seat back, the seat bottom, and the 3 loose boards. Because I put things together pretty tightly, mine fit with only about a half inch gap in the middle. You can overhang the loose boards on either end if it won’t fit. When you have everything laid out to your satisfaction, place the remaining 4 hinges. You should connect the seat bottom to the third board from each end of the sandbox. Attach the hinges with screws provided or 1 inch wood screws.

This shows how to lay out the top. Notice the boards are not attached.

Here is the placement of the hinges. The hinges are attached, but the end boards still are not attached.

Finally, make one final arrangement of the pieces so they are squared and even. You should have 2 sets of 7 boards connected together with hinges, and 2 boards on each end. You only have a few screws left. Now, using the 1/8th inch bit, pre drill the final holes. There should be 24 of them. I did one board at a time since things could be bumped, so I’d drill guide holes, switch bits and attach a board, and then switch and drill more guide holes. I also started with the third board that is attached to the hinge and worked toward the end of the sandbox.

I just need to screw down those last two boards. You can see I used the 2x6s that happened to be a bit warped for the end boards because they’ll be less obvious and they’ll be screwed down. It is noticeable in picture 1 of this post where 2 boards were notoriously difficult!

The lid is pretty heavy on the sandbox, so I also wanted to add some sturdy handles. My friend attached a rope for a handle, but I like steel handles better. To open the sandbox, I step on the end and pull the handles up and toward me until the seat is in reclining position.

One side is open.

The finished sandbox: But where’s the sand, Dad?

The very last step is to attach the handles. I placed them very near the bottom of the 2x4s (bottom meaning the end that will sit on the ground). The lid of the sandbox is too heavy for a child to open, but with the handles in this position, my wife can step on the end of the sandbox and pull the handles up and toward her to open it.

26 Comments

Thanks. Our yard gets a lot of afternoon sun, so that should help. I’m considering adding a layer of pea stone under a weed mat to help with drainage. We’ll see how t goes. Got the materials today! Thanks for posting!

How well does the cover keep the sand dry during rain or when being hit by sprinklers? We have a sprinkler system, so the sandbox will “see” water about every other day. I’m wondering if I should plan to use a tarp or something else to keep the sand fairly dry.

The sand will definitely stay more moist even without rain or sprinklers because the sun can’t dry it out. Slightly damp sand is actually must more fun in the sandbox, but watch it closely! The last thing you want is mold to grow in your sand, which can become unhealthy for your little ones. I’m not certain of your situation, but it might be a good idea to keep it as dry as possible under those conditions.
~UAF

My 16 year old son and I completed this for our 3 year old son this weekend. The directions were perfect! Thanks! We did go larger 8 by 8. We added a third hing on each side. We also put 4 bench legs on each side to support the 8 foot width as well as a kick board on each side. The only challenge that I have to think through is that the cover is too heavy for my wife to open and close. Thinking of adding a winch LOL. Thanks for taking the time to write such great instructions and pictures!

Thank you so much for showing your project and putting in the details on how to make it. I just finished one for my 2 year old son and it came out great! For anyone interested, I used 30 bags of play sand for mine and I think it’s enough.

Thank you for your post I was very helpful and easy to follow when I did my own sand box. The only thing I changed was the handles. I drilled a 7/8″ hole about an inch deep in the bottom of where the handles go then continued through with a 1/4″ hole the rest of the way. I then used a 6′ rope (1/4″ rope) I ran the rope through each hole and tied a knot in each side and the knots fit in the 1′ hole. I have back issues and this saves me from bending over to open and close the sandbox.

I filled it to 8″ and used 1cubic yard of sand. $20

I have sloping ground and the legs rest against side of the box. in time I will fill in some dirt around it, but there is no issue at the moment.

Thanks so much for posting these instructions. I do have two questions that I am hoping you might be able to give me some insight.

1. I am having trouble finding 2″ x 6″ x 10’s. Do you think 1″ x 6″s sufficiently hold the weight of the sand and people seating on the bench? This should also reduce the weight of the lid by almost half and may allow some children the ability to open it themselves.

2. How did you make sure that the bench legs rested on the ground? Can you cut them after completing the build to hit the ground? The ground outside my sandbox location may be sloping and I think the legs may need to be different lengths to accommodate this.

Well, the first thing to note is that 2 x 6s aren’t actually 2 inches wide, just like a 2 x 4 isn’t 2 inches wide. It is actually closer to 1.5 inches wide.

I think a 1 x 6 would make a fine cover for the sandbox, but I’m not sure I would trust it to hold an adult’s weight, though a child would be fine. That being said, when you actually sit on the bench, the boards are doubled up (see the headline photo).

I also wonder if children like my three rambunctious boys might play on the thinner lid (mine often use the covered sandbox as a life raft next to the larger pirate ship playset) and damage it. If you decide to go this route, please let me know how it works out by leaving a comment to advise our readers!

As for the bench legs, you could leave them a bit longer and cut them down later if you had a circular saw (I don’t think you’d have the maneuverability on a miter or “chop” saw). You have to prop the bench up at a 90 degree angle so that you’d have a fairly level surface, but I can see that working if you were extremely careful– probably a 2 man job to hold the bench and carefully saw.

I should also note, I made my legs slightly longer which allowed them to settle a bit. So if you look closely at the area the bench legs rest, they’ve worn their own grooves in the ground. Don’t cut them too short so that they can’t settle a bit (1-2 inches).

Thanks for taking on this project! I hope you have many fun hours in the sand!

Unfortunately, no. My friend and I built twin sandboxes. We took his full-sized truck and had a full front-end loader scoop of sand dumped in the back. This filled both sandboxes and there were a few wheel barrows full leftover. Unfortunately, I haven’t got any idea other than “a little less than half a truckload.” Quick math tells me 8′ x 5′ x 11″ is nearly 40 cubic feet. Of course, it is not filled to the brim…

Wow a truckload of sand!! That sounds awesome in itself. We were actually thinking about the storage option too. We thought by putting another hinge on the underside of the last 2 boards (obviously not screwing them down). This would leave only the third board from the end to be screwed down though, so I’m not sure if the constant opening and closing of the lid will be too much pressure on it.

Thanks for responding!! That is what I thought. We bought our wood today and cut it. Painting will begin tomorrow. Thanks so much for sharing this awesome project! Can I have your opinion, should I think about adding a piece of wood to prevent sand from going under the seating area? Or did you find this to not really be a problem?

I hadn’t thought about placing an end board under the seat. I got a whole truckload of sand and split it with a neighbor, so we actually shoved sand up under the benches because we didn’t have anything else to do with it. You certainly could buy 2 more 2x6s and cut them to fit inside under the benches. They’d have to be slightly less than 5 feet long (measure across the inside for the exact length) and you could screw them in from the outside. It would definitely save some square feet of sand that really can’t be played with anyway. Now you’ve got me thinking about how that area could be used for storage for toys accessed from the outside. Hmmmm….

Love the sandbox and heading to the store to pick up the supplies tomorrow. Should I buy 3 or 4 of the 8 foot long 2×6 boards? Doing the math if I do 30″x4 and 14.5″x4 I should be able to cut those all from 2 of the 2×6 boards then use a third board for the corner supports. I’m just wondering if I’m missing something. Thanks in advance!!! So excited to get started.

Well, if your sandbox is the same size as mine (8′ x 5′) you need to buy 4 2x6s that are 8 feet long. They serve as the 8 foot sides. You’ll need 11 2x6s that are 10 feet long. You’ll cut those in half to make 22 5-footers, four of which go on the end, and 18 of which go on top.

The 2x4s are a separate issue. These are used for the corner supports, armrests, and back supports. You’ll could do it with 3 2x4s. You would cut 2 of them as follows: 2 sections of 30 inches each (uses up 60 inches). 2 sections of 14.5 inches each (uses up 29 inches). That would use 89 inches of 2 of your 2x4s. You’d use the third 2×4 for the 11 inch corner pieces.